1. Field of the Invention
The present invention relates to a picture storage device linkable to a data input device.
2. Description of the Related Art
The names of files of pictures stored in a digital still camera are determined in accordance with a predetermined camera file system employed by the digital still camera, such as the Design rule for Camera File system (DCF) by the Japan Electronic Industry Development Association (JEIDA).
FIG. 1 shows an example a file system for storing picture files in accordance with the DCF.
As shown in FIG. 1, in the DCF, under a root directory 1301, a digital camera images (DCIM) directory 1302 is formed, and below the DCIM directory 1302, each directory 1303 (hereinafter referred to as the “DCF directory 1303”) is formed. Below the DCF directory 1303, each picture file is stored as each file 1304 (hereinafter referred to as the “DCF file 1304”) which is named in accordance with predetermined rules.
A DCF directory name assigned to the DCF directory 1303 consists of eight characters. The first to third characters are numbers that are not repeated, that is, “100” to “999”. These numbers are called “directory numbers”. In each directory number, the fourth to eighth characters are arbitrary one-byte capital alphabetic characters.
A DCF directory name assigned to the DCF directory 1304 consists of a three-character extension and an eight-character file name. In this file name, the first to fourth characters take an arbitrary character string using only one-byte numerals and capital alphabetic characters. The fifth to eighth characters take numbers from “0001” to “9999”. These numbers are hereinafter referred to as “file numbers”. The three-character extension represents an image format type. FIG. 1 shows a case in which the image format type represents the JPEG (Joint Photographic Experts Group) format. When the image format type is the JPEG format, the extension is “JPG”.
In addition, below the root directory 1301, a directory having a directory name other than a DCF directory name may be formed. FIG. 1 shows that a directory 1305 having the directory name “MISC” is formed.
An image captured by a digital still camera can be played back by another digital still camera if both cameras employ a file system such as the DCF.
Also, recently, there is great need to play back images stored in a digital still camera by using an image playback device other than the digital still camera, such as a cellular phone or a personal digital assistant.
In order to play back an image by means of an image playback device into which a removal memory cannot be loaded, a method which provides close-range radio-communication means to a digital still camera and the image playback device has been proposed. In this method, by using the close-range radio communication to establish a link between the digital still camera and the image playback device, the image stored in the digital still camera can be played back by the image playback device.
In general, the image playback device does not support a file system in accordance with a predetermined camera file system such as the DCF. Thus, when the image stored in the digital still camera is played back by the image playback device by using the close-range radio communication, both the digital still camera and the image playback device must be provided with rules that can uniquely determine an image file.
By way of example, as FIG. 2 shows, by designating an image file 1401 by using a series of figures composed of directory numbers and file numbers, the image file 1401, which is named in accordance with the DCF, can uniquely be determined.
Image file names determined by the series of figures (1402) composed of the directory numbers and the file numbers are hereinafter referred to as “image handles 1402”. Since the directory numbers are unique values, by designating one of the image handles 1402 composed of the directory numbers and the file numbers, a short length of seven numerals can specify an image.
The image playback device uses the close-range radio communication to link to the digital still camera, and can play back a desired image by using one of the image handles 1402 for image designation.
Nevertheless, in the case in FIG. 2, if the image handle 1402 for use in designating the desired image is referred to, the content of the desired image cannot be known until it is played back since the image handle 1402 is constituted by only numerals.